[William Noble]

sniip


5. I have done tests where I lined up a pile of power amps, for example,
a
10 watt Leak, a 35 watt Fischer, a 60 watt dynaco, a 350 watt kenwood -
using the speakers I had at the time (AR-3) and the music I liked at the
time (don't remember what I used), there was no question that the quality
of
the resultant sound improved with power - the low end went from muddy to
crisp. A 700 watt amp that I tried was one notch better, but beyond my
budget. I'm not going to debate this, you may hear differently, this is
what I hear, at the same very soft volume level.

Using the amps that you used, I suspect that the Leak, probably the
Fisher,
and perhaps the Dynaco (unless it was a ST120 rather than a Mk.III, you
don't
say) were tube (valve) amps. if so, the bass quality difference has as
much
to do with output transformers in the tube gear vs solid-state (the
Kenwood
and perhaps the the Dynaco - if its a solid-state amp), as it has to do
with
power.

you may well be correct about the root cause of the improvement - I actually
expected the Leak to sound the best, it certainly had the best reputation.
As I think back, I think I had two dynacos - one was a 50 watt tube unit
(mono), the other was a stereo 120. Nonetheless, tubes or not, with my
speakers (AR3a) and my source (marantz 7T and a turntable - I don't remember
the cartige now), sound quality, particularly at the low end, at VERY SOFT
volume, was directly proportional to power. As I stated somewhere else,
this finding was the exact opposite of what I expected, and I repeated it
over and over to prove it to myself, so I doubt that preconceived bias had
much to do with the conclusion

6. "properly" designed amplifiers is a completely undefined term, and
there
is no way to define it. You can write specifications, as voluminous as
you
want, and most folks will easily hear differences between amplfiers that
conform to all your specs, whatever you choose to write in them. So, when
the OP said "properly designed", he/she basically asked a non-question.
Once you crawl out of the "consumer grade" stuff, it is your personal
preference for a particular coloration that will help you decide which
unit
you like.

Modern, solid-state amps sound practically identical, irrespective of
cost.
What differences that their might be are truly subtle and minute. While
some
audiophiles are willing to pay megabucks for amps that sound so close to
their much cheaper cousins, that the differences are more imagined than
actually experienced, for all practical purposes, the differences (if
discernible at all) disappear into total unimportance after a few minutes
of
listening. The important part of choosing an amplifier these days is to
get
one with enough power for your particular speakers and your listening
preferences with regard to playback level.

the statement above about "practically identical" is misleading. it all
depends on what you mean by "practical". When I bought my Mark Levison
power amp (No 332), it replaced my trusty Kenwood 700M - they have
aproximately equivalent power and seemingly similar specs, though the ML
unit is quite a bit heavier. The difference was clearly audible. I tried
other power amps also, some sounded better still, but I didn't feel they
were worth the $$. I would argue that all of the amps I listened to were
"properly" designed, but there were clearly audible differences. My test CD
for all of these tests was a song from Gillian Welch's Hell among the
yearlings album, played very softly - in no case would it have been hard to
talk in a normal voice and be clearly heard - I used ReQuest speakers for
the test - maybe some amps don't like those speakers, but it was what I've
got.

So, I can't argue subjective experience, I can only report my experience. I
do agree that the power amp is one of the parts that has the least overall
effect once you get a "good enough" one, and that the improvement going from
a $500 amp to a $250,000 amp is smaller by far than is gained by going from
a $500 preamp to a $5000 preamp.

[Sonnova]

On Tue, 14 Oct 2008 05:35:00 -0700, William Noble wrote
(in article ):

sniip


5. I have done tests where I lined up a pile of power amps, for example,
a
10 watt Leak, a 35 watt Fischer, a 60 watt dynaco, a 350 watt kenwood -
using the speakers I had at the time (AR-3) and the music I liked at the
time (don't remember what I used), there was no question that the quality
of
the resultant sound improved with power - the low end went from muddy to
crisp. A 700 watt amp that I tried was one notch better, but beyond my
budget. I'm not going to debate this, you may hear differently, this is
what I hear, at the same very soft volume level.

Using the amps that you used, I suspect that the Leak, probably the
Fisher,
and perhaps the Dynaco (unless it was a ST120 rather than a Mk.III, you
don't
say) were tube (valve) amps. if so, the bass quality difference has as
much
to do with output transformers in the tube gear vs solid-state (the
Kenwood
and perhaps the the Dynaco - if its a solid-state amp), as it has to do
with
power.

you may well be correct about the root cause of the improvement - I actually
expected the Leak to sound the best, it certainly had the best reputation.
As I think back, I think I had two dynacos - one was a 50 watt tube unit
(mono), the other was a stereo 120. Nonetheless, tubes or not, with my
speakers (AR3a) and my source (marantz 7T and a turntable - I don't remember
the cartige now), sound quality, particularly at the low end, at VERY SOFT
volume, was directly proportional to power. As I stated somewhere else,
this finding was the exact opposite of what I expected, and I repeated it
over and over to prove it to myself, so I doubt that preconceived bias had
much to do with the conclusion

AR3s? That explains it. 15 Watts is nowhere near enough power to satisfy the
requirements of an AR3. It was a VERY inefficient loudspeaker that required,
IIRC, at least 25 watts/channel to drive it. The leak was likely clipping
most of the time! Of course it sounded bad.

6. "properly" designed amplifiers is a completely undefined term, and
there
is no way to define it. You can write specifications, as voluminous as
you
want, and most folks will easily hear differences between amplfiers that
conform to all your specs, whatever you choose to write in them. So, when
the OP said "properly designed", he/she basically asked a non-question.
Once you crawl out of the "consumer grade" stuff, it is your personal
preference for a particular coloration that will help you decide which
unit
you like.

Modern, solid-state amps sound practically identical, irrespective of
cost.
What differences that their might be are truly subtle and minute. While
some
audiophiles are willing to pay megabucks for amps that sound so close to
their much cheaper cousins, that the differences are more imagined than
actually experienced, for all practical purposes, the differences (if
discernible at all) disappear into total unimportance after a few minutes
of
listening. The important part of choosing an amplifier these days is to
get
one with enough power for your particular speakers and your listening
preferences with regard to playback level.

the statement above about "practically identical" is misleading. it all
depends on what you mean by "practical". When I bought my Mark Levison
power amp (No 332), it replaced my trusty Kenwood 700M - they have
aproximately equivalent power and seemingly similar specs, though the ML
unit is quite a bit heavier. The difference was clearly audible. I tried
other power amps also, some sounded better still, but I didn't feel they
were worth the $$. I would argue that all of the amps I listened to were
"properly" designed, but there were clearly audible differences. My test CD
for all of these tests was a song from Gillian Welch's Hell among the
yearlings album, played very softly - in no case would it have been hard to
talk in a normal voice and be clearly heard - I used ReQuest speakers for
the test - maybe some amps don't like those speakers, but it was what I've
got.

Of course the ML sounded better than the Kenwood. You just bought it, paid a
ton of money for it, and your expectations were high. New is always going to
sound better than "old" that's why sighted evaluations - especially by the
owner of the new gear - are so unreliable. Connect those amps to your
speakers using an A-B switching device, match the levels to within 1/4 of dB,
and have someone else randomly switch between them (where you can't see them
doing it) while you listen, and then come back and tell us which amp was
which. As long as neither amp is being driven outside of its capabilities and
as long as the Kenwood (which, I take was rather old, since Kenwood hasn't
been sold here for many years and is called "Trio" in the rest of the world)
is in original working order (no tired capacitors) then I doubt seriously if
you could tell the difference.

So, I can't argue subjective experience, I can only report my experience. I
do agree that the power amp is one of the parts that has the least overall
effect once you get a "good enough" one, and that the improvement going from
a $500 amp to a $250,000 amp is smaller by far than is gained by going from
a $500 preamp to a $5000 preamp.

I'm not even sure that's particularly true.

[Jean]

the statement above about "practically identical" is misleading. it all
depends on what you mean by "practical". When I bought my Mark Levison
power amp (No 332), it replaced my trusty Kenwood 700M - they have
aproximately equivalent power and seemingly similar specs, though the ML
unit is quite a bit heavier. The difference was clearly audible. I tried
other power amps also, some sounded better still, but I didn't feel they
were worth the $$. I would argue that all of the amps I listened to were
"properly" designed, but there were clearly audible differences. My test CD
for all of these tests was a song from Gillian Welch's Hell among the
yearlings album, played very softly - in no case would it have been hard to
talk in a normal voice and be clearly heard - I used ReQuest speakers for
the test - maybe some amps don't like those speakers, but it was what I've
got.

Hello,
i had a pair of Quests a few years ago, their impedance goes down
below 2 Ohms in the treble, many amplifiers can't handle them. I had
an Accuphase P 300 (2x150 w) and on some records at certain moments
the protection circuits would shut it down. I'm not surprised the M
Levinson did the job well.
Best regards,
Jean